Heater for fluids



u. M. LUEHRS. HEATER FOR FLUIDS.

APPLICATION FILED OCT- 7; 1920.

Patented July 26, .1921.

PATIENT oFFicE.

.DANIEL M. tonnes, or CLEVELAND, 'onro.

HEATER FOR FLUIDS.

' Specification of Letters Patent.

Patented July 26, 1921.

Application filed October 7, 1920.. Serial No. 415,362.

To all whom it may concern:

Be it known that 'I, DANIEL M. LUEHRS, a citizen of the United States,residing at Cleveland, in thecounty of Cuyahoga and State. of Ohio,have'invented, certain new and useful Improvements in Heaters forFluids, of which the following is a specification. i v T This inventionrelates to a heater for heating, fluids in transit, and it comprises adrum or casing having a spiral channel of considerable depth extendingfromits periphery to its center, and heating units, in the form of rodsor'tubes, arranged at suitable intervals throughout the length of thechannel. These units aresecuredto one or both heads of the drum andextendtransversely of the channel, preferably spaced fromits spiralwall, so that the fluid flowing through. the channel will come in directcontact with all parts of the several heating elements. The spiralchannel has several convolutions, and as the fluid to be heated flowsfrom the outer convolution toward the center, it accumulates heat fromthe heating units in its path. Little or no loss of heat occurs byconduction through the spiral wall of the channel, since the incomingcooler fluid in an outer convolution takes up any heat transferredto thechannel wall from the hotter fluid in an inner convolution.

The heating units are preferably electric resistance rods, removablysecured in one head of the casing and readily replaceable in case a unitbecomes defective. I may, however, employ as heating units thin metaltubes extending through both heads of the drum and adapted to be heatedby the passage of hot gases through the tubes.

In the accompanying drawing,

Figure 1 is an end view of a heating drum embodying my invention, a partof the drum being shown in central section and the spiral channel beingindicated in dotted lines; and,

Fig. 2 is a side elevation of the same, partly in section, most of theheating units being omitted, for the sake of clearness of illustration.I

Referring to the drawing, A indicates a cylindrical casing or drumhaving heads 1 and 2, the latter being removable and secured to a flange3. Within the casing is a spiral wall or partition 4, which'extends, in

width, .from head to head of the drum, and in length, from an inletopening 5 in the peripheral wall of the drum to an outlet opening 6 atthe center of one of the heads. The several convolutions of the spiralwall are substantially parallel with one another, and the spiral channel7, formed by the wall and the casing, is rectangular in sec tion,hav-ing considerable width, measured between the casing heads,as-compared with its depth, measured between the convolutions of thespiral wall.

'The head 2 is provided with a spirally arranged series of openings,through which heating units in the form of electric resistance rods 8are extended intothe channel. These rods, as shown in the drawing,

pass through stufling boxes 9 in the head 2 and aresupported by saidhead. The rods extendtransversely' of the channel and are supportedclear of the spiral wall in order that the fluid to be heated may flowpast the rods in contact w'ith their entire surfaces. The openings forreceiving the rods are spaced at suitable intervals throughout thelength of the channel, as shown in the drawing, and as the rods arereadily removable, any desired number of rods can be employed, accordingto the temperature to which it may be desired to raise the fluid. Ofcourse, when a rod is removed, the corresponding opening in the headwill be plugged. The temperature also may be controlled by leaving therods in position and connecting or disconnecting the circuits of therods; but preferably when a unit is not to be used it will be withdrawn,in. order not to impede the progress of the fluid through the channel.

The heating units may be supported in both heads of the drum, ifdesired, and also, where electric current is not available, or forcertain purposes, instead of employing electric heating units, I may usehollowrods or tubes of thin metal, extending through both heads andadapted to be heated by the passage of hot gases through these tubes.

It will be evident that when the fluid to be heated, such as oil orwater, is passed in at the inlet opening 5, it will flow in contact withthe successive heating units to the outlet 6, accumulating heat fromsaid units as it flows toward the center of the drum. Any heat conductedthrough the spiral wall from an inner convolution will be taken up bythe cooler fluid in the immediately surrounding convolution. Thus, sincethe flow of fluid is from the periphery toward the center, practicallyno loss of heat occurs by conduction through the spiral wall. The bodyof the drum and its heads may, of course, be suitably insulated toprevent the loss of heat. This being a common expedient, it is notillustrated in the drawing.

What I claim is:

1. A heater for fluids comprising a drum having openings at itsperiphery and center and having a spiral channel connecting saidopenings, and heating units spaced apart in said channel.

2. A heater for fluids comprising a drum having openings at itsperiphery and center and having a spiral channel connecting saidopenings, and heating units, secured to an end wall of the drum andextending into said channel.

3. A heater for fluids comprising a drum having openings at itsperiphery and center and having a spiral channel connecting saidopenings, and heating units, secured to an end wall of the drum andextending into said channel, said units being spaced apart from oneanother and spaced from the spiral walls of the channel.

4. A heater for fluids comprising a drum having openings at itsperiphery and center and having a spiral channel connecting saidopenings, and heating rods extending into said channel through an endwall of the drum, at suitable intervals apart.

5. A heater for fluids comprising a drum having openings at itsperiphery and center and having a spiral channel connecting saidopenings, and heating rods extending into said channel through an endWall of the drum, at suitable intervals apart, said rods being spacedfrom the spiral walls of the channel.

6. A heater for fluids comprising a drum having openings at itsperiphery and center and having a spiral channel connecting saidopenings, and heating units removably secured in an end wall of the drumand projecting into the channel.

7. A heater for fluids comprising a drum having openings at itsperiphery and center and having a spiral channel connecting saidopenings, the walls of the channel being substantially parallel, andheating rods extending transversely of the channel and spaced apart fromone another.

8. A heater for fluids comprising a drum having openings at itsperiphery and center and having a spiral channel connecting saidopenings, the walls of said channel being substantially parallel, andheating rods extending transversely of the channel and spaced apart fromone another and from said spiral walls.

In testimony whereof I aflix my signature.

DANIEL M. LUEHRS.

